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41.
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis.  相似文献   
42.
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction.  相似文献   
43.
Talar dome lesions greater than 1 cm in diameter are often treated with ankle joint mosaicplasty. The purpose of this article is to present the use of a noninvasive ankle distractor that can improve access to the talus when used with a malleolar osteotomy. The use of the distractor allows for graft insertion at a more appropriate angle in relationship to the talar cartilage, avoidance of invasive distractor usage, and potential use of a smaller osteotomy.  相似文献   
44.
OBJECTIVE: Persistent vertigo and imbalance can occur after surgery for vertigo regardless of surgical approach. This study explored for factors affecting outcome of vertigo surgery. STUDY DESIGN: Patient survey and chart review. SETTING: Tertiary referral neurotologic private practice. PATIENTS/INTERVENTION: Of 111 patients (57.7% female; mean age, 52.3 yr), 59 underwent vestibular nerve section (middle fossa, retrolabyrinthine, and translabyrinthine), 25 underwent transmastoid labyrinthectomy, and 27 underwent endolymphatic sac shunt. Eighty-three percent had Ménière's disease. Mean follow-up was 4.3 years. MAIN OUTCOME MEASURES: Primary outcomes included American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) vertigo score and class, number of spells per month, current and change in AAO-HNS disability rating, vertigo and imbalance severity ratings, and frequency of imbalance. RESULTS: Three preoperative factors were consistently related to outcome: AAO-HNS disability rating, imbalance frequency rating, and duration of first symptom ([rho] = 0.19-0.51; all p's < 0.05). Greater disability and more frequent imbalance related to poorer outcome, but longer duration of disease related to better outcome. Presurgery vertigo characteristics were generally not related to outcome. Ménière's patients were more likely to have improvement in imbalance, as were those with no other significant disease and no allergy. The presence of tinnitus in the contralateral ear was associated with poorer outcomes, including a lower rate of results of Classes A and B (p = 0.023). Vertigo as a first symptom and the presence of eye disease also showed relationships to poorer outcome. CONCLUSION: Those rating themselves as more disabled before surgery are less likely to achieve the best outcomes, whereas frequency and severity of preoperative vertigo are not predictive. Several possible prognostic factors were identified that warrant future prospective study.  相似文献   
45.
46.
Abstract Prevention of caries in exposed root surfaces constitutes an important clinical problem. It is thus important that clinicians involved with periodontology have an insight into fluoride prophylaxis. The understanding of the cariostatic mechanism of fluoride has improved during recent years. The aim of the present review is to give a short account of the present concept. Calcium fluoride appears to be the only product which is formed on enamel, dentin or cementum during brief topical treatments with fluoride or use of toothpaste containing fluoride. This calcium fluoride is stable in the oral environment: this is contrary to what was believed until recently. The calcium fluoride constitutes a pH-dependant reservoir of fluoride which releases fluoride when pH drops. The practical consequences of this concept is discussed.  相似文献   
47.
Endocarditis secondary to Hemophilus parainfluenzae is an uncommon entity that appears to be increasing in frequency, perhaps due to improved laboratory isolation techniques. Although controversial, most of the published literature recommends a penicillin, with or without concomitant gentamicin, as definitive therapy. We report the first successful use of the third-generation cephalosporin ceftizoxime in an ampicillin-allergic patient. A 55-year-old white female was hospitalized after 5 days of experiencing fever, chills, nausea, and vomiting. A cardiac echocardiogram revealed a large mitral valve vegetation, and the patient was treated with intravenous ampicillin, gentamicin, and clindamycin. Two weeks after emergency mitral valve replacement the patient developed spiking fevers and a macular, erythematous rash while receiving ampicillin. Ceftizoxime was initiated and continued to complete a 4-week period of intravenous antibiotics. Follow-up at 14 months showed no further evidence of infection. Ceftizoxime appears efficacious in eradicating H. parainfluenzae in patients allergic to penicillin.  相似文献   
48.
L-2-Hydroxyglutaric acid (LGA) is the biochemical hallmark of patients affected by the neurometabolic disorder known as L-2-hydroxyglutaric aciduria (LHGA). Although this disorder is predominantly characterized by severe neurological findings and pronounced cerebellum atrophy, the neurotoxic mechanisms of brain injury are virtually unknown. In the present study, we investigated the effect of LGA, at 0.25-5mM concentrations, on total creatine kinase (tCK) activity from cerebellum, cerebral cortex, cardiac muscle and skeletal muscle homogenates of 30-day-old Wistar rats. CK activity was measured also in the cytosolic (Cy-CK) and mitochondrial (Mi-CK) fractions from cerebellum. We verified that tCK activity was significantly inhibited by LGA in the cerebellum, but not in cerebral cortex, cardiac muscle and skeletal muscle. Furthermore, CK activity from the mitochondrial fraction was inhibited by LGA, whereas that from the cytosolic fraction of cerebellum was not affected by the acid. Kinetic studies revealed that the inhibitory effect of LGA on Mi-CK was non-competitive in relation to phosphocreatine. Finally, we verified that the inhibitory effect of LGA on tCK was fully prevented by pre-incubation of the homogenates with reduced glutathione (GSH), suggesting that this inhibition is possibly mediated by oxidation of essential thiol groups of the enzyme. Considering the importance of creatine kinase activity for energy homeostasis, our results suggest that the selective inhibition of this enzyme activity by increased levels of LGA could be possibly related to the cerebellar degeneration characteristically found in patients affected by L-2-hydroxyglutaric aciduria.  相似文献   
49.
50.
Cholinergic synaptosomes from electroplax of the ray Ommata discopyge release both ATP and ACh when depolarized with high K+ concentration in the presence of Ca2+. Others have shown that the ATP and ACh are released in the molar ratio found in isolated synaptic vesicles. Thus, it is assumed that the release of ATP reflects exocytosis of synaptic vesicles, and that transmitter release can be indirectly monitored by assaying ATP release. We present further evidence for this assumption and examine the effects of presynaptic neurotoxins on this ATP release. As expected for transmitter release, we find that depolarization-evoked ATP release is supported by Sr2+ and Ba2+ and is inhibited by the Ca channel antagonists Co2+ and Mn2+. Likewise, the presynaptic toxins omega-CmTX and omega-CgTX, omega peptides from the venom of the marine snails Conus magus and Conus geographus, respectively, inhibit 80% of the depolarization-evoked ATP release. Half-maximal inhibition of ATP release occurs with approximately 0.5 microM of either toxin. The toxins' effects are reversible, and when toxin is washed away, the time dependence of recovery of release is approximately first order and half complete within 40 min with omega-CmTX and 15 min with omega-CgTX. The Ca2+ ionophore A23187 induces Ca2+-dependent ATP release from resting synaptosomes. As would be expected of a Ca channel antagonist, omega-CmTX does not affect this ionophore-induced release. Leptinotarsin-d (LPTd), a putative Ca channel agonist from the Colorado potato beetle, evokes Ca2+-dependent ATP release from resting synaptosomes. omega-CmTX does not block LPTd-evoked release of ATP, which suggests that omega-CmTX and LPTd act at different sites.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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